effect modifier

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ef·fect mod·i·fi·er

a factor that modifies the effect of a putative causal factor under study; for example, age is an effect modifier for many conditions.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Table-IV: Effect modifier like Hemorrhagic startification with with QTc Prolongation.
Effect modifiers represent various study and patient characteristics that are also associated with the patient characteristics.
Chi square test was used to compare the safety between the two groups Also safety was stratified among the age and gender to see the effect modifiers. P[?]0.05 was considered significant.
We agree that both breast-feeding and organic mercury exposure may affect neurodevelopment and have the potential to act as confounders and/or effect modifiers in analyses of metal effects on neurodevelopment.
In the pooled trial analysis of estrogen plus progesterone and estrogen alone, metabolic syndrome was found to be an effect modifier. The odds ratio for treatment effect was 0.98 for women without the metabolic syndrome and 1.72 for those with the metabolic syndrome.
We evaluated the role of the potential effect modifiers (sex, age, SES at the census block level, chronic and acute conditions as previously defined) via conditional logistic regression models stratified by the levels of each presumed effect modifier: we compared the effect estimate for [NO.sub.2] in each category of the potential effect modifier with the effect estimate in the reference category for the potential modifier, from the stratified models.
One potential effect modifier in these studies is genetic variability in pesticide metabolism.
For each (hypothesized) effect modifier, a city-specific logistic regression model was fitted and an overall estimate calculated in a subsequent meta-analysis.
Fat in the diet appears to be an important effect modifier when coupled with exposure to air particulate pollution."
Body weight differences between male and female animals were not observed among all offspring, within diet groups, or within coat-color classes, consistent with sex not being an effect modifier of the relationship between body weight and diet or coat color.
The remaining effect modification patterns were not so clear, with lines crossing over the range of the relevant effect modifier. The curve corresponding to the 25th percentile of the N[O.sub.2] (24-hr) distribution is steeper from the level of 50 [micro]g/[m.sup.3] until the level of approximately 150 [micro]g/[m.sup.3], whereas in the range from 20 to 50 [micro]g/[m.sup.3] the slope of the curve corresponding to the 75th percentile is steeper.
Correlations between biomarkers of exposure and effect with disease outcomes will facilitate the process of identification of variants that act as effect modifiers. As with any scientific endeavor, intriguing results in this area of research need to be replicated in different studies and populations to confirm the role of a variant as an effect modifier.